PROJECT SUMMARY Language Impairment is one of the most common communication disorders treated by speech-language pathologists. The disorder is characterized by impaired development of spoken language that cannot be attributed to hearing loss, intellectual disabilities, or other known neurological deficits (Benton, 1964). Treatment provided to children with LI relies heavily on the provision of corrective feedback. However, such a teaching method may not be optimal because abnormalities in brain circuits that support feedback-based learning have been reported in children with LI. More specifically, the same brain circuits that have been implicated in implicit learning (basal ganglia and in particular the striatum), and have been found abnormal in function or structure in children with LI, have also been implicated in feedback-based learning. The proposed study is a critical first step in establishing whether learning is disrupted in children with LI by the need to process corrective feedback. It will also assess the benefit of providing children with LI with a learning environment that does not rely on feedback processing. Children will perform two probabilistic classification learning tasks, one with feedback (feedback- based) and the other without feedback (paired-associate). The project will examine behaviorally and at the neurophysiological level the effects of corrective feedback on the learning of children with LI in comparison to their peers. It will compare learning outcomes (accuracy level on test trials immediately following the task and a week after the task) and strategy use (single cue vs multi-cue) in children with LI and those with TD under the two learning conditions. It will also compare the activation of a neurophysiological marker of feedback processing (i.e., the Feedback Related Negativity) during the feedback-based task between children with LI and those with TD. This is the first study that evaluates the effect of corrective feedback on learning outcomes and learning strategies in children with LI. The neurophysiological measure serves to examine the intactness of the neural generator of a brain potential linked to feedback processing. Since this neural generator has been implicated in implicit learning, findings will shed light on the relationship between feedback processing and implicit learning in children with LI. Understanding whether children with LI learn better with or without the need to process corrective feedback will lead to improvement in the teaching techniques employed with children with LI, and to the development of effective intervention that takes into consideration these children?s unique learning profile.